Aluminium has many useful properties. Accordingly, it is second in production, after iron and steel. Because the density of aluminium is low, it is used for forming many strong alloys that contain relatively small percentages of silicon, copper, manganese, magnesium, and zinc. These alloys, with their light weight and high strength, are preferred for use in many industries like automotive, consumer durables, utensils etc. The thermal conductivity and the electrical conductivity is the third highest; just lower than silver and copper. Aluminium is also non-magnetic. Thus, its high ductility makes it available in rolled, extruded, forged, drawn forms. Aluminium may be easily machined and its low melting point makes it suitable for casting and superior quality die castings. It is commercially available in forms such as plates, sheet, and bars, rolled sections, pipes, wire, and foil. Aluminium is highly resistant to corrosion under usual conditions in the atmosphere and in water.
Owing to these useful properties, worldwide aluminium manufacturing capacity in the year 2000 was approximately 20 million metric ton/yr and it is still growing with the demand.
Aluminium is manufactured from the intermediate compound e.g. alumina, which is obtained from the ores like bauxite, available in the earth crust. In an electrolysis process, alumina, Al2O3, is dissolved in a bath of molten cryolite, Na3AlF6, aluminium fluoride, AlF3 is used to reduce the melting point of liquid bath, which includes Caf2, Al2O3 and Cryolite. The mixture is subjected to an electrolysis process in electrolysis cells (pots) connected in series, and liquid aluminium is produced at the cathodes. The carbon anodes are oxidized and bubble away as carbon dioxide. The chemical reaction as a whole is represented by the chemical equation given below:2Al2O3+3C→4Al+3CO2 
The liquid aluminium product settles at the bottom of the bath, as molten aluminium is heavier than cryolite. The molten aluminium is periodically tapped from the bottom. At the top side of the bath cryolite forms a solid crust. This solid crust is broken by punching it with crust breakers. Gas evolved in the process escapes from holes formed in the broken crust. These holes also facilitate charging of fresh ore to the bath in the pot. While operating a set of electrolyzing pots connected in series, it many times happens that all the pots can not be put on line simultaneously. Some of the pots may be kept isolated out of the circuit while others in the line are running. The isolated pots are taken on line after they are made ready for running (for example completion of the maintenance work on them).
The present disclosure is related to taking the off line pots online while the pot line is running. Background art is described in the light of the above information with reference to figures, are briefly described below. Though all the figures are described in the section “Brief description of figures” the figures relevant to the background art only are described here again for the sake of convenience to the reader.